Rewind machine



United States Patent 6/1949 Schnell Primary Examiner-Stanley N. Gilreath Assistant Examiner-Werner H. Schroeder Attorney Fryer, Tjensvold, Feix, Phillips and Lempio ABSTRACT: In a rewind machine for converting rolls of wide webs of material into a plurality of narrower strips wound on independent rewind rolls, uniform tension of the narrow strips on their associated rewind roll is achieved through special roll support arms which independently support each rewind r011 core in a manner that the engaging force between each rewind roll and a common driving platen remains essentially constant as the diameter of the rewind rolls change. A special core support cradle on each rewind arm provides for convenient and independent changing of the individual rewind rolls, without interference with the other rewind rolls.

mm "nu 4467 Patented Nov. 10, 1970 3,539,121

INVENTOR CHARLES E; GRAWEY ATTORNEYS REWIND MACHINE BACKGROUND OF THE INVENTION In many manufacturing operations, strip material is first formed in wide, thin webs or belts which then are subsequently converted into narrow strips by slitting and rewinding the material on independent rolls. Often when converting the webs to narrower strips, it is required that the internal tension and density of the strips on the rewind roll be very consistent to reduce irregularities when they are subsequently utilized on other machine operations.

To achieve commercially acceptable rewind rolls, in which tension and density are consistent, slitter and rewind machines often employ complex and complicated driving systems on the rewind roll to obtain uniform density and tension of the strips wound on the rewind roll. An example of such drives is disclosed in US. Pat. No. 3,198,453 issued to Aaron.

Through this invention, it is now possible to eliminate such complicated drives for the individual rewind rolls, in certain applications, and maintain uniform consistency in density and tension on the strip materials wound on the rewind roll. Elimination of such drives facilitates convenient and simple exchange of the individual rewind roll and substantially reduces the total cost of the slitter and rewind machinery necessary to produce a commercially acceptable rewind roll. In addition to a substantial reduction in the total cost of the slitter and rewinding machinery, the invention allows independent control of each rewind roll and independent replacement at any time so that further economies are experienced through reduced labor costs.

SUMMARY OF THE INVENTION The invention is an improved slitter rewind machine for converting wide belts of material into a plurality of narrow strips wound on separate cores comprising a frame having a pedestal means mounted thereon for supporting a roll of such wide belt material, brake means between said pedestal means and said roll to control the tension of said belt from said roll, control and tension sensing means coupled to said brake means and operable to adjust the same to maintain uniform tension on said belt, a powered platen means mounted on said frame for receiving said belt and pulling it from said roll, knife means mounted adjacent to said platen means and urged against said platen to slit said belt into a plurality of narrow strips, a plurality of core means, one for each strip supported against and in engagement with said platen, and a plurality of support arms swingably mounted on said frame, one support arm for each core means, each of said arms mounted so that the contact force between said platen and the roll forming on its core means remains substantially constant as the roll diameter increases. Each of the core means is supported in a novel cradle assembly at the outboard end of each arm which makes its removal and replacement simple and convenient and represents a further improvement.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevation of the novel slitter rewind machine with parts broken away to show its threading detail;

FIG. 2 is a top view of the platen and rewind rolls of the front end portion of the machine;

FIG. 3 is a perspective of the outboard end of one of the support arms with parts broken away and illustrating the fiberglass rewind core cradled in the outboard end of thearm; and

FIG. 4 is an elevation of the end of a support arm with parts broken away to show how the core is supported.

DESCRIPTION OF AN EMBODIMENT The instant invention was designed for slitting webs of rubberized cloth-type materials into narrow strips. A typical. example of such materials are webs or sheets prepared by calendering rubber on one or both sides of an open mesh fabric base from which a plurality of individual rubberized fabric tapes can be made.

Basically, thenovel rewinding machine includes an elongated frame or bed 11 having a pedestal unit 12 at one end and a slitter-rewinder assembly 13 at the other.

The pedestal unit includes two spaced-apart upright support posts 14 with journals 15 adjacent to their tops for supporting shaft 16 of the roll 17 of the wide web material 18 to be slit into narrower strips. For controlling the payout of the web from the roll, a detachable band brake assembly is associated with the shaft and employed to effect unwinding of the roll under uniform tension. Of course, other types of brakes, or similar devices could be employed to control the roll payout as described. I

In the illustrated embodiment, two semicircular brake bands 20 surround the shaft 16 near one end and are anchored to a common lug 21 on one of the pedestals so that their clamping action on the shaft, effected by actuator 19, will insure payout of the web from the roll under uniform tension. The actuator is controlled through a connection to a modulating control unit 23 via line 24.

The modulating control unit iscoupled to a tension transducer 25 through a wiring conduit 26 and operates the actuator to maintain uniform tension on the belt 27 of the web material leaving the roll 17. This belt is threaded under an idler roller 28, across support rollers 29 and under protective plate 30 to the tension idler roller 31 which is swingably mounted on its opposite ends on arms 32 pivoted on the frame structure.

One of the roller support arms 32 on the tension idler roller v is connected by a linkage 33 to the tension transducer unit 25 which contains a strain gauge (not shown) or similar device for measuring the force exerted on this roller. Since the belt 27 of the web material extends upward after tracking around the tension idler roller, the force transmitted to the transducer is proportional to the tension on the belt. Thus, a signal generated by the transducer unit can be used to operate the brake assembly through the modulating unit to maintain a constant tension on the belt. The tension on the belt can be changed by appropriate adjustments on the control system and brake assembly. I

From the tension idler roller, the belt passes upward to the upper idler roller 34 located adjacent to a cylindrical platen 35 so that the top of the idler roller is above the bottom of the platen. Threading the belt over the idler roller and then under the platen and'partially around it insures a good driving relationship between the belt and the platen. This threading arrangement is shown in FIG. 1.

The platen is normally a stainless steel roller and is driven through a drive mechanism 36 by motor 37 which may be located in any convenient place on the machine for driving a platen. Utilizing the threading arrangement previously described, the belt 27 is pulled off the roll 17 supported by the pedestal unit through its frictional drive with the platen. Thus, by controlling the payout from the roll through the tension transducer unit, the belt is uniformly disposed on the platen.

The belt is wrapped around the platen for approximately and during this contact, a plurality of roller knives 36 or slitting knives, are urged against the belt circumferentially wrapped on the platen, to slit the web into a plurality of strips which are to be subsequently wound on the rewind rolls. Usually, these knives are supported from acontrol unit 37 and areheld against the platen with springs or pneumatic devices with mechanisms (not shown) within the control unit. Normally, they are retractable to facilitate threading the belt.

Tension in the belt is maintained at a constant value from v the widebelt to the platen by means of the modulating brake. The uniform tension is maintained in the rewound roll because the tension in the roll is the same as that which exists in the strip while on the surface of the platen.

After the knives cut the belt into a plurality of strips, these strips are taken off the platen by a plurality of similar rewind roll assemblies 40. The rewind assemblies are mounted on the frame of the machine, one for each strip cut from the belt, so adjacent strips are removed on opposite sides of the platen, as best illustrated in FlG. 2. Each rewind assembly includes an adjustable base support 41 having a pivot pin 42 swingably supporting an arm 43 with a cradle assembly 44 in its outboard end. The base is adjustably secured to the frame in end slots with mounting bolts 45 so that each individual arm can be properly adjusted.

In each cradle, a hollow fiberglass core 46 is mounted so that its axis is parallel to the axis of the platen and the base of each arm retains it on the machine so that the arms can swing the core against the platen as shown in FIG. 1. The fiberglass cores are supported in the cradle assembly in a manner that they can be easily lifted out once the rewind roll has reached the desired diameter. Initially, each rewind roll is started by attaching one of the strips to the core and placing the core in the appropriate arm so that the core is supported by or rests on the platen. During this initial loading operation, the strip is carefully wound on the core and the arm swung toward the platen so that no looseness of the strip on the core exists.

Arranged in this manner, each rewind roll is driven directly from the platen at its periphery and changes speed accordingly as the diameter of the rewind roll changes. A plurality of arms assures that all rolls of tape may increase in diameter at varying rates, depending upon the gage of the sheet in each location. For example, if the wide belt is .001 inches thicker on one side than on the other, 100 layers of this sheet would produce a variation of .l inch in the radii of the two rewound rolls. These different diameter rolls would still maintain uniform tension since the roll is wound from the surface by the material on the platen roll. In FIG. 1, for purposes of illustration, two different size rewind rolls are illustrated, showing that different size rewind rolls may be taken off of the platen simultaneously. Such flexibility often prevents the loss of strips should an unexpected parting of the strip occur.

in order to maintain wrap consistency, the geometry of the mounting of each rewind arm 43 is constructed and adjusted so that a contact force between each rewind roll and its driving platen remains essentially constant as the diameter of the rewind roll changes. This feature is very important and insures achieving a commercially acceptable rewind roll of strip material.

Generally, the base of each rewind roll assembly must be located on the frame so that as the roll diameter and weight increase, the increased weight is distributed between the platen and the pivot support of the arm, in a manner that the contact force between the platen and the roll does not change substantially. In the instant design, l-inch wide rubberized fabric was wound on rewind rolls and the force between the rewind roll and the platen measured as the diameter of the rewind roll increased from the core diameter of to l8 inches in diameter. During this period, the force remained between 9.6 and 9.8 pounds and produced a rewind roll with uniform tension and good wrap consistency. Of course, there are outer limits to the roll size which canbe conveniently made and in this test situation, as the roll in the machine increased to 24 inches, the contact force decreased to 7.5 pounds.

The support of the core of each rewind roll is illustrated in FIG. 3 and rollers 50 are used to support the core (shown in FIG. 4). Three rollers are mounted on each side of each rewind arm 43 to support the cylindrical core 46 on which the narrow strips cut from the web or belt are wound. Each rewind arm is composed of two separate spaced apart plate members 51 which have an arcuate recess at their outboard ends about which the rollers are mounted, as can be seen in the drawings.

Three rollers are located around the arcuate recesses in each plate member so that they will contact the cylindrical core within a l80 sector, with two of the rollers closely spaced near the bottom of the arcuate recess in order to carry the weight of the rewind roll as the strip material is wound thereon.

Each roller is constructed with a flange 53 outboard of its peripheral support race 54 and mounted on a separate ball bearing 55 journaled on small stub shafts 56, projecting from their associated support arms. So mounted on the support arm, the rollers support the core on their peripheral races and the flanges overlap the ends of the core so that no shifting can occur as the core is driven by its contact with the driven platen. This peripheral support of the core and endwise retention thereof improves the overall stability of the core during the rewind operation and insures a more uniform wrap.

Spacing of the rollers about the arcuate recess is important and, generally, the two lower rollers are spaced equally on opposite sides of the longitudinal axis of their associated arm. Using the center of the core as a point, the centers of the two lower rollers are located on lines having an included angle of approximately 30 with the longitudinal axis of the arm. However, this spacing may vary somewhat with the diameter of the core being employed.-

The upper roller is located within approximately of the lower outboard roller so that no binding will be experienced when cores are changed in the cradle assembly formed by the rollers.

In essence, the raised flanged portions of each of the rollers forms a guide which prevents any shifting of the core as the strip material is wound thereon. The arrangement makes removal of the filled core and its replacement with an empty core simple, and eliminating the need for special shims and bosses for center core support, necessary if peripheral support is not employed. This allows the hollow opening in the core to be any dimension so that it can be conveniently sized to the subsequent machine in which the roll is to be employed.

()ther methods of end side retention include elimination of one or more of the support roller flanges with end side support provided by other means such as a retaining pin. The choice between flange retention or other end side retention is a matter of preference for ease in assembly and disassembly. The rollers may be replaced by split spring-loaded bearings which would be opened for quick replacement of the core and when such spring-loaded device is used, more than of the core can be supported. These means use a sliding support of the core rather than a rolling support and the choice between these will depend on the tension at the belt.

The rewind rolls 60 formed on each core can be removed from the machine by swinging the outboard ends of arms 43 away from platen 35 after the roll is filled with strip material to the position indicated by broken lines 61 in FIG. 1. From this position, the rewind roll can be lifted out of the cradle formed by rollers 50 and a new core replaced for starting another roll.

I claim:

1. A slitter rewind machine comprising:

a frame having a pedestal means for supporting a roll of material to be slit into a plurality of narrow strips;

adjustable brake means associated with said pedestal means for restraining. the unwinding of said roll;

a powered platen means mounted on said frame for receiving material wound on said roll and pulling it from said roll;

tension sensing means located between said pedestal means and said platen means and connected to said adjustable brake means whereby the tension of said material between said pedestal means and said platen means is maintained essentially constant by controlled operation of said adjustable brake means;

a plurality of knife means mounted adjacent to said platen on said frame and resiliently urged against said platen to slit said material into narrow strips;

a plurality of rewind cores for taking up the resulting strip material in driving engagement with said powered platen means; and

a plurality of core support arms swingably mounted on said frame and having bearing means for supporting an associated rewind roll core, each bearing means including a plurality of wheels located about an arcuate recess in the outboard end of each arm, said wheels supporting its associated core on their peripheral surfaces and having a projecting radial flange for endwise restraining its core, and each arm having a mounting geometry so that the force between a roll forming on its core and the platen remains essentially constant as the roll diameter increases.

2. The slitter rewind machine defined in claim 1 wherein the tension sensing means includes an idler roller connected to a transducer whereby a signal is generated proportional to the tension of the material between the pedestal means and the powered platen means. v

3. The slitter rewind machine defined in claim 1 wherein the core support arms are alternately located on opposite sides of the platen.

4. A support arm for a rewind core on rewind machines which cores are drivingly engaged by the platen for winding the rewind roll comprising an adjustable base for attachment to the 'machine adjacent to the platen, an arm swingably mounted on said base witbspivot means having an axis parallel to the axis of said platen, said arm having a mounting geometry which maintains the contact force between its associated core and the platen substantially constant as the diameter of the rewind roll increases, a core support cradle located in the outboard end of said arm including an arcuate recess for receiving a rewind roll core and a plurality of wheels located around such recess for supporting said core about its periphery, said wheels having projecting radial flanges for endwise retention of said core. 

